A 5-year-old Cumberland County mare is the first reported case in 2017 of Eastern equine encephalitis (EEE), a serious mosquito-borne illness.

The horse had not been vaccinated against EEE and died on Aug. 28.

“Horse owners need to be vigilant in vaccinating their animals against diseases spread by mosquitoes,” said New Jersey Secretary of Agriculture Douglas H. Fisher. “Vaccinated animals are much less likely to contract deadly diseases such as EEE and West Nile virus.”

The disease is transmitted by bites from infected mosquitoes. The virus cycles between birds and mosquitoes with horses and humans being incidental dead-end hosts. Horses cannot transmit EEE to humans or vice versa